Having a water skin will also help - instead of taking the damage, you "are forced to drink" from it.

(From Bugs): There are 3 kinds of danger squares. Those that do 5 damage and cost 5 base AP, those that do 10/10 and those rare ones that do 20/20. A water bottle reduces the damage, boots reduce the AP cost, but there is no way to completely reduce a cost of 20AP.